Izifudumezi ezijikelezayo zifakwe ngaphakathi komkhumbi ovalwe ngokushisa okushisayo okudlula uketshezi noma igesi.Okuqukethwe kuyashiswa njengoba kugeleza kudlule into yokushisisa, okwenza izifudumezi zomjikelezo zilungele ukushisisa kwamanzi, ukuvikela iqhwa, ukushisa amafutha okudlulisa ukushisa, nokunye.
Izifudumezi ezijikelezayo zinamandla, izifudumezi zikagesi ezisemlayini ezakhiwe ngepulaki eliyisikulufa noma umhlangano we-tubular ogxunyekwe nge-flange ofakwe ethangini lokuhlangana noma umkhumbi.Uketshezi olungacindezelwe noma olucindezelwe kakhulu lungashiswa ngempumelelo kakhulu kusetshenziswa ukushisa okujikelezayo okuqondile.